Unsaturated keto esters as insecticides



Patented'Dec; 15, 1942 UNITED STATES PATENT OFFICE.

UNSATURATED KETO ESTER'S AS I INSECTICIDES Richard '0. Roblin, Jr., and William Moore, Stamford, Conn., assignors to American Cyan-' amid Company, New York, N. Y., a corporation of Maine No Drawing. Application April 9, 1940,

Serial No. 328,692

9Claims. (01. 167-22) I The present invention relates to insecticides and more particularly to a class of compounds which are especially effective as contact poisons for the control of insect pests.

The invention is based upon the discovery that unsaturated keto esters of the general formula:

OH: R f 040 I R coca" in whichR is selected from the class consisting of hydrogen, aliphatic and aromatic radicals, R is selected from the class consisting of hydrogen,

, CH: I H 04o @040 o Q CH: H a o I O-c :=O +1110 cooozm The following examples illustrate in detail the preparation oi representative compounds of the invention. Materials employed are in parts by weight.

EXAMPLE 1 25 parts of benzaldehyde and 50 parts of 2- ethylhexylacetoacetate were mixed together and cooled to -15 C. Zparts of piperidine were addedas a catalyst. The mixture was allowed to I stand for 48 hours at 510 C. Water had separated atthe end of this period. The mixture was then dissolve in ether, washed neutral with 0.05% sulphur c acid, dried over sodium sulphate and distilled. The benzal-2-ethylhexylacetoace decylacetoacetate was recovered as a yellow-green phenone-ethylacetoacetate separated from the -acetoacetate were mixed together, cooled to 0 C.

tate was recovered as a slightly green viscous oil, boiling-at 167 C. at apressureof 1 mm.

A EXAMPLE 2' Y 30 parts of benzaldehyde and parts of lauryl and treated with 2 parts of piperidine. The mix ture was held at 5-10 C for 12 hours, then al lowed to stand 24 hours at room temperature, after which it was treated according to the procedure followed in Example 1. The benzallaurylacetoacetate was recovered as a yellow-green oil, boiling at 170 C. at 0.4 mm. pressure.

EXAMPLE 3 17.5 parts of benzaldehyde and 50 parts of tetradecylacetoacetate' were mixed together, cooled to 0 C. and treated with 2 parts of piperidine. The mixture was held at'5-10 C. for 12 hours, then allowed to stand 48 hours at room temperature after which it was treated according to the procedure followed in Example 1. The benzaltetraoil, boiling at C. at 0.4mm. pressure.

EXAMPLE 4 A mixture of 20 parts of a-n-amyl cinnamic al-. dehyde, 13 parts of ethylacetoacetate and 1 part of piperidine was allowed to stand at room temperature for 24 hours. Considerable water had separated at the end of this period. The reaction product was treated according to the procedure followed in Example 1. The a-n-amylcinnamalethylacetoacetate was recovered as a slightly yellow oil, boiling at 182 C. at less than 1 mm. pressure. z

EXAMPLE 5 Tea solution of .2 part of metallic sodium dissolved in 5 parts of alcohol were added 8 parts of ethylacetoacetate, 11.5 parts of ci'nnamalacetophenone and 60 parts of ether. The mixture was allowed to stand for 12 hours atroom temperature, after which time the cinnamalacetosolution as a colorless crystalline solid. .Aiterrecrystallization from alcohol th product .melted at 106 C.

EXAM LE 6 A mixture of 40 parts of heptaldehyde, 45 parts of ethylacetoacetate and 3 parts of piperidine was allowed to stand at 10 C. for 40 hours. The reaction product was treated according to the procedure followed in Example 1. The heptylideneethylacetoacetate was recovered as a colorless oil boiling. at -180 C. at 1 mm. pressure.

EXAMPLE 7 '70 parts of ortho-chlorobenzaldehyde and 65 parts of ethylacetoacetate were mixed together and cooled to 15 C. 1 part of piperidine was added during the course of one hour. The mixture was kept at 15 C. for 48 hours, then held at 5-10 C. for 24 hours, after which it was Example 1. The o-chlorobenzalethylacetoacetate was recovered as a colorless liquid boiling at 142 C. at less than 1 mm. pressure.

EXAMPLE 8 was placed in a suitable vessel and heated under a reflux condenser for 6 hours in an oil, bath. The temperature of the bath was 125 C. The react-ion mixture was cooled to 0 C., neutralized with with water. The ether extract was dried over sodium sulphate, and the residue, after removal of the ether, was distilled under reduced pressure. The chlorylidene-ethylacetoacetate was recovered as a colorless liquid, boiling at 110-115 C. at less than 1. mm. pressure.

The compounds of the present invention are characterized by increased toxicity in comparison in which the solvent medium is a liquid consisting of 65% acetone and 35% water, the figures in the following tables represent the kills under complied to the citrus red spider:

Table 1 Compound Dilution Kill Per cent Ethylacetoacetate 1- 500 0 Table 2 Compound Dilution Kill Per coal.

Benzalethylacctoacctate 1- 500 r00 Benzalbutylacetoacctate 1-2000 1100 Bouzallaurylacetoacetate l 1-1000 1100 Do i 1-2000 M. 3

Benzaltetradecylacctoacctat I 1-2000 1100 Do 1-4000 01.1 Do 1-8000 000 l A 100 per cent kill of the rrvl spider eggs is obtained in conjunction with the. 100 per cent kill of the active forms.

It is believed that the benzal-2-ethylhexylacetoacetate. benzallaurylacetoacetate and hence]- tetradecylacetoacetate are new compounds. As shown above in Table 2, these substances are especially active insecticides for use against the red spider in that they destroy both the active forms and the eggs in one operation.

In regard to other compounds of the present sodium hydroxide, dissolved in ether and washed with the simple alkyl esters of acetoacetic acid. N Thus, with the compounds incorporated in a spray parable conditions at various dilutions when apcitrylidene ethylacetoacetate, l-naphthalethyltreated according to the procedure followed in A mixture of 50 parts of chloral, 44 parts of I ethylacetoaceta-te and 35 parts of acetic anhydride acetoacetate, o-chlorobenzalethylacetoacetate, an-amylcinnamalethylacetoacetate, p-chlorobenzalethylacetoacetate, furfuralethylacetoacetate, cinnamalethylacetoacetate, chlorylidene ethylacetoacetate, heptylidene ethylacetoacetate, crotylidene ethylacetoacetate, m-nitrobenzalethylacetoacetate, ethylidene ethylacetoacetate, cinnamalacetophenone ethylacetoacetate, methylene ethylacetoacetate, vanillalethylacetoacetate, isobutylidene ethylacetoacetate, and isopropylidene ethylacetoacetate.

These new insecticides may be applied in any of the conventional manners. Thus. for example, they may be incorporated in liquids for spraying purposes, or they may be effectively used in dusts with such inert solid diluents as kieselguhr, wood flour, walnut shell, talc and the like.

While the invention has been described with particular reference to specific embodiments, it is to be understood that it is not to be limited thereto but is to be construed broadly and restricted solely by the scope of the appended claims.

We claim:

1. An insecticide containing a toxic amount of a compound of the general formula:

in which R, is selected from the class consisting of hydrogen, aliphatic and aromatic radicals, R is selected from the class consisting of hydrogen, aliphatio' substituted aliphatic, aromatic, substituted aromatic and aralkyl radicals, and R is an aliphatic hydrocarbon radical.

2. An insecticidecontaining a toxic amount of a compound of the general formula:

in which R is selected from the class consisting of hydrogen, aliphatic, substituted aliphatic, aromatic, substituted aromatic and aralkyl radicals, and R" is an aliphatic hydrocarbon radical.

3. An insecticide containing a toxic amount of a compound of the general formula:

in which R is an aromatic radical, and R" is an aliphatic hydrocarbon radical.

l. An insecticidal composition including a toxic amount of benzal-2-ethylhexylacetoacetate.

5. An insecticidal composition including a toxic amount of benzallaurylacetoacetate.

6. An insecticidal composition including a toxic amount of benzaltetradecylacetoacetate.

7. Benzal-2-ethylhexylacetoacetate.

8. Benzallaurylacetoacetate.

9. Benzaltetradecylaceoacetate.

RICHARD O. ROBLIN, J R. WILLIAM MOORE. 

